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5-1
Section
Connecting to the Host’s RS-422A/485 Port
72
Item
Setting at Host
Parity
Even
1-to-1/1-to-N
1-to-N
(*2)
Command level
Level 1, 2, 3
*1 Set the Host Link baud rate at 9,600 bps or 19,200 bps with the Comm. Speed
memory switch at the NT21. For details, refer to Setting the Host Link Method
(page 125).
*2 The 1-to-N setting enables BCC (Block Check Character). It is not actually
possible to connect more than one NT21 in a single Host Link.
Set the CPU Bus Unit settings directly from a Programming Device (e.g., SYS-
MAC Support Software).
For details on the CPU Bus Unit settings, refer to the SYSMAC CVM1/CV-series
Host Link Unit Operation Manual (W205-E1-
j
).
Setting the Front Switches
Communications port 1
(RS-232C)
Communications port 2
(RS-232C/RS-422A)
I/O port selector switch
RS-422A
@
Unit # (SW3, SW4)
Set these switches to 0.
@
Communication condition setting (pin 1)
Set this pin to OFF.
Communication is executed in accordance with the
CPU Bus Unit system settings made at the PC. The
initial values for the system settings are as follows.
- Baud rate: 9,600 bps
- Parity: Even
- Xon/Xoff control: Not executed
- Communication method: Full duplex
- Stop bits: 2 stop bits
- Data length: 7 bits
@
I/O port selection (selector switch)
Set this to RS-422A.
RS-232C
@
Terminating resistance setting (selector switch)
Set this to ON.
Connecting to a CJ-series Serial Communications Unit
CJ-series: CJ1W-SCU41 (Port 1 is an RS-422A/485 port.)
Setting the Front Switches
Set the unit number of the Serial Communications Unit with the rotary switch on
the front of the Unit. Set the unit number with a flat blade screwdriver. Also, set